Used solar panels: Are they a good idea?

Some of the lowest prices for solar equipment can be found on sites like eBay, where people can post their used solar panels for sale at a discounted price. We'll examine the used solar panel market and whether buying panels from a reseller is the best option for your home solar power setup.

For most solar installations, your installer will include brand-new parts, from panels to inverters to wiring. But a quick online search for used solar panels (also called solar modules) will show you several buying options for secondhand equipment, including bidding sites like eBay, wholesale used panels from several vendors, and even Amazon listings. Panels may be sold secondhand for several reasons: they may be slightly damaged, leading to lower efficiency, or someone may have purchased too many panels. No matter the reason for the sale, used solar panels can be enticing for their low prices and low-stakes utility in DIY solar projects.

The main advantage of used solar panels over newly manufactured ones is their lower cost. Used panel prices can be as low as $0.10 to $0.75 per watt compared to an average of $2.86 per watt for new solar panels in the U.S. on EnergySage. However, there are many things you should consider when purchasing used solar panels other than their initial cost.

While used solar panels might be a good fit for specific projects, for most solar customers, they present more problems than they're worth. There are several reasons used panels might not be the right decision for you, including:

1. Used panels have already degraded

Used solar panels will often produce less energy than advertised because, over time, the output of a solar panel drops incrementally. This doesn't necessarily mean your used solar panels are damaged – it's just a normal part of the wear and tear process on the equipment. But, the higher your initial system output, the more you'll save long-term with your solar energy system.

2. Used panels are often damaged

Many large commercial solar projects will include damaged panels from time to time, and owners will minimize financial losses by reselling them at a discounted price. Unfortunately, if your used solar panels are damaged, they won't produce as much energy, and you'll save less on your electricity bills. Damaged panels are less efficient, meaning they don't convert sunshine as efficiently into useful electricity. So, under the same conditions, a damaged and less efficient solar panel will produce less electricity than a new and more efficient solar panel of the same size.

3. Solar technology is continuing to improve

The solar industry constantly develops and sells new panel technologies at competitive prices. Even a used panel in good condition from a few years ago will have outdated photovoltaic technology and produce electricity less efficiently than a new solar panel. For this reason, you save more money over time by installing newer, more efficient, and often higher-watt solar panels instead of paying less upfront for an outdated model.

For example, most new solar panels installed today are monocrystalline, meaning they include solar cells made from a single crystal of silicon and are more efficient. On the other hand, used solar panels may be polycrystalline, with solar cells made from many silicon fragments melted together and tend to be more affordable. You'll want to weigh options to fit your needs best; an experienced installer can help you before purchasing.

4. Used panels may not include warranties

Most solar manufacturers will provide both production and equipment warranties when you purchase a solar energy system, guaranteeing that your panels will remain free from defects and maintain a certain percentage of their original output. For example, SunPower offers the leading warranty for home solar panels, which guarantees 98 percent of original output by the end of the first year and 92 percent by year 25 (if installed new).

Used panels don't always have the same warranties attached, and you may leave yourself risking lower solar production or failure without any coverage. Additionally, there's often no way to verify that used solar panels even work or output a certain wattage in the first place, meaning you could end up purchasing completely broken or unusable equipment.

5. Used equipment might not qualify for incentives

When you install a new solar system to harness renewable energy at your home, you'll qualify for the investment tax credit (ITC), which allows you to deduct 30 percent of your system costs from your federal taxes. However, the U.S. Department of Energy (DOE) notes on its website that "the solar PV system is new or being used for the first time to qualify for this incentive. The credit can only be claimed on the original installation of the solar equipment."

For some homeowners, used solar panels may be a smart purchase. For example, if you don't want to power your whole home with solar and instead are looking for a way to charge a small battery, buying a few used panels is a low-stakes, inexpensive way to get your energy. Overall, the smarter long-term decision for most people is to install a brand-new solar system that can provide power to your home for years to come. Many homeowners shopping with EnergySage look at various factors to find the best quality and value with solar equipment, not just the best price. You can check out our Solar Panel Equipment Guide to compare solar panels based on our expert rating system.

If you're looking to install a solar system on your roof, as a carport, or as a ground mount system, buying used solar panels often creates more problems than it solves. Fortunately, on the EnergySage Marketplace, you easily get quotes for new systems from verified installers at competitive prices. If finding the lowest price for solar is your priority, note in your account that you're looking for inexpensive options so installers can tailor their quotes to your preference.